Field of the Invention
The invention relates to a wide-angle lens.
Description of the Related Art
Digital camera and cell phone have been continuously developed toward high pixel and weight reduction. Therefore, the requirements for wide-angle lens with high pixel and miniaturization are greatly increased. The well-known lens assembly with three lenses usually uses one lens with low Abbe number which is close to the image side, two lenses with high Abbe number and an aperture before the first lens in order to meet the requirements of miniaturization and high resolution. However, the field of view of well-known lens assembly is relatively small. When the temperature reaches 60° C. or the length between the object and the lens assembly is equal to 300 mm, the resolution of the lens assembly will become worse. Therefore, a lens assembly needs a new structure in order to enhance the characteristics described above and meet the requirement of the present.